We have a 2018 293RKDS with the same thing. Plug you indicate I believe is for accessories on the awning as the plug for your curb side activity should be inside your pass through storage compartment with an access port that comes out the bottom of the compartment. I did not discover that right way either.
How many of you think some of Geniuses at Jayco should have to spend at least 2 weeks living in what they manufacture ?? If they did I bet you we would see a lot of simple and not costly changes made to all of the RVs they manufacture.